Heating and Air Conditioning: Description and Operation

HEATING AND AIR CONDITIONING




GENERAL DESCRIPTION
The heater system uses a two-way-flow full-air-mix system that features high performance and low operating noise. It includes an independent face air blowing function. In addition, an air purifier has been included.

OPERATION

CONDENSER FAN AND RADIATOR FAN CONTROL
The PCM judges the required revolution speed of radiator fan motor and condenser fan motor using the input signals transmitted from A/C switch, output shaft speed sensor and engine coolant temperature sensor. The PCM activates the fan control relays to drive the radiator fan motor and condenser fan motor.

COMPRESSOR CONTROL

When operating the air conditioning switch
- The air thermo sensor, which senses the temperature of the air flowing out of the evaporator, deactivates the compressor at 5 °C (41.0 °F) or below.




- The dual pressure switch turns OFF when the refrigerant pressure becomes excessively high or low, thus protecting the compressor circuit (See Table).
- When the air thermo sensor is activated, the dual pressure switch is ON, and the ignition switch, blower switch, and air conditioning switch are ON, the A/C Compressor Clutch Relay is energized.

When operating the air outlet changeover control knob
- When the air outlet changeover control knob is moved to DEFROSTER or DEFROSTER/FOOT position, the defroster switch, which is connected in series to the air conditioning switch, is turned on. The other compressor control than the above is the same as that when operating the air conditioning switch.